When a plurality of moving machines are remote-controlled at the same place by utilizing infrared radiation or radio waves and communication is carried out between the moving machines by utilizing infrared radiation or radio waves, signals transmitted from the transmitter to the moving machine and signals between the moving machines interfere with each other, and therefore, there is the fear that accurate control and communication will be difficult. As a technique solving such a problem, for example, the system disclosed in Japanese Patent No. 2713603 is well-known. In this system, a transmitter has a transmitting device which transmits, by radio waves, data for remote-controlling a corresponding moving machine. Further, the moving machine has a transmitting device which transmits, by infrared radiation, data for communicating with another moving machine, a device which receives data by radio waves, and a device which receives data by infrared radiation. In accordance therewith, a remote control operation system is realized in which signals transmitted from the transmitter and signals from the moving machine are prepared from interfering with each other, and a plurality of moving machines are remote-controlled at a same place, and communication between the moving machines is carried out.
In the above-described remote control system, a moving machine needs two different receiving devices, which are a device which receives radio waves transmitted from a transmitter and a device which receives infrared radiation transmitted from another moving machine, and a processing system. Therefore, the drawbacks that the structure of the moving machine is complicated and the electric power consumption increases arise.